(originally sent to OWL WG; where Bijan replied, and I will follow up to
his message here)
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In my analysis of what is going in POWDER I have now written
http://www.w3.org/2007/OWL/wiki/POWDER
I have a question.
POWDER includes two properties wdr:validFrom and wdr:validUntil.
Inbetween these dates then an example like:
http://www.w3.org/2007/OWL/wiki/POWDER#Example
should 'entail'
http://www.w3.org/2007/OWL/wiki/POWDER#The_subclass_relationship
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Outside these dates the 'entailment' is not known to hold.
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Clearly a full formal treatment of time is well outside the scope of
what will be included in the POWDER specification.
So how do I hack it?
Or perhaps more positively, how do I express pragmatically the
relationships.
I have to define a semantic extension to RDF, so I have quite a lot of
wiggle room, but need to use it cautiously.
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I'll try writing a straw man and adding it to the page.
Might take an hour or two.
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Note for the DL people - I need to also articulate how my approach
relates to OWL DL.
Jeremy